In motor vehicles, “fields of view” are legally-prescribed (required by law) in accordance with the type of the motor vehicle, such as e.g., motorcycles, motor vehicles for transporting passengers, motor vehicles for transporting goods, etc. The fields of view must be provided by one or more “device for indirect viewing”, which is conventionally a mirror, and the fields of view must be visible or viewable by a driver sitting in the driver's seat using the device(s) for indirect viewing. Depending upon the type of the vehicle and, in particular, which areas around the vehicle that can be directly seen by the driver, different legal provisions require, depending upon the vehicle type, that certain fields of view can be seen at all times using the device(s) for indirect viewing.
Therefore, for commercial vehicles, such as e.g., trucks or delivery vehicles, e.g., a primary mirror is currently provided on each of the driver's side and the passenger's side as devices for indirect viewing. Using the primary mirror, the vehicle driver can see a level and horizontal part of the road surface of a certain width, which extends from a stipulated distance behind the vehicle driver's eye point up to the horizon. In addition, a band of lesser width must be visible or viewable for the vehicle driver using this mirror, which band begins at a short distance behind the driver's eye point. The area near the vehicle, which can be viewed using the primary mirror and is legally required to be always visible or viewable, will be designated in the following as the “field of view of the primary mirror”.
In addition to these two primary mirrors, fields of view provided by wide-angle mirrors are required to be seen on both sides of the commercial vehicle. Each area behind the driver's eye point is viewed using the wide-angle mirrors in a defined length in the longitudinal direction of the vehicle. Although this area is wider than the area viewable by the driver using the primary mirror; it extends only a certain (shorter) length along the side of the vehicle.
In accordance with the applicable legal provisions for implementing or providing the required fields of view, commercial vehicles further require a close-proximity mirror. Using the close-proximity mirror, an area lying in the front area next to the driver's cab and an area directly adjacent to the driver's cab are visible or viewable by the driver. Finally, for at least some types of commercial vehicles, one additional field of view is required to provided, e.g., by a front mirror. Using this additional (e.g., front) mirror, an area directly in front of the commercial vehicle, which area extends in the lateral direction of the commercial vehicle beyond the passenger-side edge of the commercial vehicle, is viewable by the driver.
However, in spite of these legally-prescribed mirrors and/or devices for indirect viewing, it is scarcely possible and/or very difficult for a vehicle driver to completely and sufficiently maintain in view at all times the areas around a commercial vehicle that are prone to accidents. Moreover, due to the plurality of mirrors, the burden on the vehicle driver to substantially simultaneously maintain all of these mirrors in view increases. Moreover, because the fields of view are provided using mirrors, the mirrors disrupt the smooth flow of air around the vehicle while driving as a consequence, such that vehicle drag is increased and thus fuel consumption is increased.
A display device is known from WO 2011/061238 A1 (post-published prior art with respect to the priority date of the present application). A device for monitoring the surroundings of vehicles having at least first and second monitoring devices is described therein. The monitoring devices output display signals to a control device. A display device connected with a control device is capable of depicting the display signals from the monitoring devices in a split-screen mode in at least two sections. The control device is connected with a state of motion signaling line so that it causes the at least two display signals from the monitoring devices to be displayed on the display device in the split screen mode in accordance with the state of motion of the vehicle.
Further, a display device is known from DE 10 2006 020 511 A1. To transmit video signals from at least one camera at the tail of a motor vehicle and/or motor vehicle trailer to at least one display unit in the motor vehicle, in particular a truck, the video signals output by the camera are digitalized and encoded, while performing a data compression in real time, and then these encoded video signals are impressed on a power supply voltage system and transmitted via the power supply voltage system. The encoded video signals transmitted via the supply voltage system are subsequently filtered out from the power supply voltage system, decoded and/or decompressed and supplied to the display unit for image rendering.